This release fixes CVE-2019-9511 "Data Dribble" and CVE-2019-9513
"Resource Loop" vulnerability in nghttpx and nghttpd. Specially crafted
HTTP/2 frames cause Denial of Service by consuming CPU time. Check out
for details. For nghttpx, additionally limiting inbound traffic by
--read-rate and --read-burst options is quite effective against this
kind of attack.
CVE-2019-9511 "Data Dribble": The attacker requests a large amount of
data from a specified resource over multiple streams. They manipulate
window size and stream priority to force the server to queue the data in
1-byte chunks. Depending on how efficiently this data is queued, this
can consume excess CPU, memory, or both, potentially leading to a
denial of service.
CVE-2019-9513 "Ping Flood": The attacker sends continual pings to an
HTTP/2 peer, causing the peer to build an internal queue of responses.
Depending on how efficiently this data is queued, this can consume
excess CPU, memory, or both, potentially leading to a denial of service.